An appropriate balance between soil air and soil water must be maintained since soil air is displaced by soil water. Air can fill soil pores as water drains or is removed from a soil pore by evaporation or root absorption. The network of pores within the soil aerates, or ventilates, the soil. This aeration network becomes blocked when water enters soil pores.
Moissanite (/ËmÉÉªsÉnaÉªt/) is the name given to naturally occurring silicon carbide and to its various crystalline polymorphs. It has the chemical formula SiC and is a rare mineral, discovered by the French chemist Henri Moissan in 1893.
Marcasite is the name given the mineral iron sulfide, which is mined all over the world. However, most of the gem called marcasite used in jewelry is actually iron pyrite, since genuine marcasite often crumbles into dust and is thus too delicate to be used in jewelry.arcasite is the name given the mineral iron sulfide, which is mined all over the world. However, most of the gem called marcasite used in jewelry is actually iron pyrite, since genuine marcasite often crumbles into dust and is thus too delicate to be used in jewelry.